- pro - mailman3.common-lisp.net

[pro] conditioning on *print-readably*
by Tamas K Papp 07 Jun '11

07 Jun '11

Hi, I am working with some structures that have quite a few elements but for most of the time are easier to interpret using a one-line summary. I would like to achieve the following: when *print-readably*, have the structure printed the usual way, eg #S(...). Otherwise use my custom unreadable summary. Eg (simplified example code): (defstruct foo a b) (defmethod print-object ((foo foo) stream) (if *print-readably* (...what-to-do-here?...) ; ?? (print-unreadable-object (foo stream :type t) (format stream "my way of printing foo with A=~A and B=~A" (foo-a foo) (foo-b foo))))) but I don't know how to call CL's built-in way of printing the structure readably in the IF clause above. Tamas

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[pro] Lisp 2's and function values.
by Matthew D. Swank 04 Jun '11

04 Jun '11

I have implemented a small fexpr interpreter in Common Lisp based on Kernel http://web.cs.wpi.edu/~jshutt/kernel.html. Right now it's a Lisp 1, but I am considering trying to make it a more idiomatic extension of Common Lisp by making it a Lisp 2. Part of the Lisp 2-ness of the Common Lisp evaluator is that the car of a form must name a function, macro, or special form. This name is either a symbol bound in the function name space, or a lambda expression. However, Kernel just requires the car evaluate to a combiner (this is what Kernel calls a generic operator). Obviously, in a Lisp 2, a symbol would evaluate to the value bound to it in the function name space. However, consider the following: ((returns-a-function) arg arg ...) Would it be reasonable to allow this as a legal form as well? I'm not arguing Common Lisp should work this way, but I seems to make sense in the context of a Kernel like evaluator. Matt

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[pro] Parallel random number generation...
by Pascal Costanza 26 May '11

26 May '11

There was recently a discussion about random number generation in Common Lisp. Here is an article that may be interesting: http://www.multicoreinfo.com/2011/05/rand/ Pascal -- Pascal Costanza The views expressed in this email are my own, and not those of my employer.

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[pro] Professional Reports
by Nico de Jager 25 May '11

25 May '11

I am looking for tips to create professional multi-page reports, invoices, etc, preferably producing standalone files like PDFs that can be emailed. Automatic page calculation would be great, and I'd like to include generated and static images (e.g. graphs and logos). The solution does not have to be open source, although most of my applications are web based for which I do prefer GNU Linux as a hosting platform (I am a LispWorks user and have both Linux and Windows licenses). I know about cl-pdf and cl-typesetting, although I have only had a fleeting glance at them. Maybe there is an easy WYSIWYG layout editor that a list member can recommend among the hordes that Google spits out. How do list members typically solve this (boring) problem with their CL applications? Regards. Nico

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[pro] need a lisp tempfile library
by Mark H. David 24 May '11

24 May '11

I think it would be nice to have a library for creating tempfiles. There's this nice writeup of one in Python for inspiration: http://docs.python.org/library/tempfile.html Is there one for Lisp?

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[pro] Fwd: Professional Reports
by Alexandre Rademaker 22 May '11

22 May '11

One possible alternative to LaTeX approach is XSL:FO approach .Using lisp to create the XML (http://www.cliki.net/XML) Take a look at http://www.w3.org/standards/xml/publishing "XSL-FO, the Formatting Objects part of XSL, is an XML markup language for describing page layout and formatting." Cheers, Alexandre Rademaker http://web.me.com/arademaker/

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[pro] Introduction to Pharen
by Daniel Weinreb 20 May '11

20 May '11

If you are ever in the need of creating PHP code, take a look at this: http://scriptor.github.com/pharen/index.html -- Dan

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Re: [pro] Help with Rendering GUIs from Lisp
by akopa＠charter.net 20 May '11

20 May '11

On Thu, May 19, 2011 at 3:33 PM, Vladimir Sedach wrote: > > Also, it appears someone has tried implementing a Morphic UI in CL > before: http://www.cliki.net/MorphiCL > Yeah, i saw that. It's kind of old and based on Squeak. The nice thing about mophic.js is that (for now at least) it's simpler than Squeak Morphic, but has enough functionality to be useful. Matt

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Re: [pro] Help with Rendering GUIs from Lisp
by Vladimir Sedach 19 May '11

19 May '11

I recommend going with Cairo. It has an interface very similar to <canvas>, and is really convenient for 2d graphics. I've used SDL before and am not a fan. If you want to support multiple OSes, you can save some time by delegating cross-platform window and input handling to GTK and just using the Cairo canvas it gives you (that's how the McCLIM GTK backend works). http://cliki.net/cl-cairo2 is the library to use, the original cl-cairo seems to have disappeared http://www.cliki.net/cl-gtk2 has GTK and Cairo bindings There's other GTK bindings listed at http://www.cliki.net/GTK%20binding Also, it appears someone has tried implementing a Morphic UI in CL before: http://www.cliki.net/MorphiCL Vladimir PS - Sorry for breaking threading with this reply; I've switched off digest mode and this shouldn't happen in the future.

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[pro] Help with Rendering GUIs from Lisp
by Matthew Swank 19 May '11

19 May '11

I am porting the Morphic GUI tool kit, Or more specifically the subset that is implemented in morphic.js: http://www.chirp.scratchr.org/blog/?p=34. I am a little overwhelmed by the options for rendering the GUI to screen. The JS implementation uses html5 canvas elements where Canvases, Images, and Contexts are rolled into or are part of the same object. In am a relative novice in graphics programming, so it's hard for me to differentiate among the merits of the various bindings available to common lisp to do this. However, using the html canvas code as guide, I am gravitating towards some sort of high level canvas that writes to a lower level back end (vecto -> lispbuilder-sdl, cl-cairo). Does anyone have guidance on the best way to approach this? Should I consider "raw" SDL surfaces, perhaps with SDL_ttf for font rendering? Is OpenGL a reasonable option for what is essentially a 2d environment? Matt

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